Process of treating electrical resistances to stabilize their resistance



Patented Feb. 27, 1923.

FREDERICK R. PARKER, OF CHICAGO, ILLINOIS.

PROCESS OF TREATING ELECTRICAL RESISTANCES TO STABILIZE THEIR RESISTANCE.

No Drawing. Original application filed January 8, 1920, Serial No. 350,249. Divided and. this application filed July 23, 1920. Serial No. 398,559.

T 0 a-ZZ whom it may concern.

Be it known that I, FREDERICK R. PARKER, a citizen of the United States of America, residing at Chicago, in the county of Cook and State of Illinois, have invented a new and useful Process of Treating Electrical Resistances to Stabilize Their Resistance, of which the following is a specification.

This application is a division of my patent application Serial No. 350,249, filed January 8, 1920, on electrical protective apparatus, which was originally filed under Serial No. 361,354, on March 8, 1907. Application Serial No. 350,249 issued into Patent No. 1,350,329, on Aug. 24, 1920.

.This present invention relates to electrical resistance elements, and in particular to an improved process of treating such elements to stabilize their resistance.

The principal object of this invention is to stabilize the resistance of certain electrical resistances which have heretofore had unstable resistance.

Other objects will be apparent from the following specification.

Certain electrical resistance elements, especially those made of some form of carbonaceous material or other aggregated comminuted material, with or without a percentage-of non-conducting material, are obers can be stabilized, or kept practically the same, by passing suflicient electrical current through the resistance elements in suit able manners. The current to be passed through such a resistance element to stabilize or set the resistance thereof for a certain of the resistance element must be as great as or greater than" the maximum current density to be carried by the said element in service, or the heating eflect of such stabilizing current must be as great as or greater than the maximum heating eifect of currents to be carried by the said element in service. This stabilizing of the resistance of such a resistance element may be done by passing a large current through the resistance element for a considerable length of time, or by passing a large current through the resistance element for a shorter length of time, or by passing a smaller current through the resistance element for a greater length of time, depending on the conditions. The preferred manner of treating such resistance elements, however, to stabilize their resistance, is to send through each element a current larger than the currents to be sent therethrough in service, and leave such larger current in the element longer than the smaller currents will remain therein in service, where it is pos .sible to do this. Any suitable means may be employed for sending the stabilizing current or currents through the resistance elements. well understood without further description thereof.-

This stabilizing treatment of the resistance element sets the normal resistance thereof to a certain value, which value will not be materially changed from time to time by lesser currents passing through the element, or by a smaller current density per unit of cross-section of the element, or by currents heating the element to a lesser-extent than the stabilizing current heated it.

A still larger stabilizing current, or agreater extent of heating, may set the normal resistance of the element to a new value. The current density of the stabilizing current, and the extent of heating, in the resistance element, are factors iii-setting or stabilizing the resistance of the element.

After the resistance elements or heating elements are treated as set forth above, to stabilize their resistance and thereby elim inate the objection thereto above noted, suflicient portions of them, or sufficient numbers of them, may be utilized in electrical circuits, in manners well understood, to give the required resistances.

I do not wish to limit this invention to It is thought that such means are lot.

the exact matter set forth in this specification, as various modifications thereof may be utilized Without departing from the scope of the appended claims.

What I claim herein as my invent-ion is:

1. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising passing therethrough a greater current of electricity than currents to be carried thereby in service. I

2. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising passing therethrough a greater current of electricity than currents to be carried thereby in service, for a longer period'of time than that to be occupied by any current to be carried thereby in service.

3. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising-passing therethrough a current of electricity of greater current density per unit of crosssection of the resistance element than currents to be carried thereby in service.

4:. The process of stabilizing the resist. ance of an electrical resistance element having unstable resistance, comprising passing therethrough a current or electricity of greater current density per unit of crosssection of the resistance element than cur- .rents to be carried thereby in service, for

a longer period of time than that to be occupied by any current to be carried thereby in service. I I

5. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising heating the said element by passing an electrical current therethrough, to a greater extent than currents to be carried thereby in service Will heat it.

6. The process of stabilizing the resistance of a carbonaceous electrical resistance element, comprising passing therethrough a greater current of electricity than currents to be carried thereby in service.

7. The process of stabilizing the resistance of a carbonaceous electrical resistance element, comprising passing therethrough a greater current of electricity than currents to be carried thereby in service, for a longer period of time than that-to be occupied by any current to be carried thereby in service,

8. The process of stabilizing the resistance oi a carbonaceous electrical resistance element, comprising passing therethrough a current of electricity of greater current density per unit of cross-section of the resistance element than currents to be carried thereby in service. v

9. The process of stabilizing the resistance of a carbonaceous. electrical resistance element, comprising passing therethrough a eia-mo current of electricity of greater current density per unit of cross-section of the resistance element than currents to be carried thereby in service, for a longer period of time than that to be occupied by any current to be carried. thereby in service.

10. The process of stabilizing the resistance of a carbonaceous electrical resistance element, comprising heating the said element by passing an electrical current therethrough, to a'grater extent than currents to be carried thereby in service Will heat it.

11. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising passing therethrough a current of electricity at least as great as'the largest current to be carried thereby in service.

12. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising passing therethrough a current of electricity at least as great as the largest current to be carried thereby in service, for a period of time at least as long as that to be occupied by any current to be carried thereby in service.

13. The process of stabilizing the resist-v ance of an electrical resistance element having unstable resistance, comprisingpassing therethrough a current of electricity of at least as greatcurrent density per unit of cross-section of the resistance element as currents to be carried thereby in service.

14. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising passing therethrough a current of electricity of at least as great current density per unit of cross-section of the resistance element as currents. to be carried thereby in service, for a period of time at least as long as that to- =be occupied by any current tobe carried thereby in service.

15. The process of stabilizing the resist-- ance of an' electrical resistance element having unstable resistance,-comprising heating the said element by passing an electrical current therethrough, to at least. as great an extent as currents to be carried thereby in service will heat it.

16. The process of stabilizing the resistance of'a carbonaceous electrical resistance element, comprising passing therethrough a current of electricity at least as great as the service. I

v17. The process of stabilizing the resistance of a carbonaceous electrical resistance element, comprising passing therethrough a current of electricity at least as great as the largest current 'tobe carried thereby in largest current to be carried thereby in serv- 18. The process of stabilizing the resistance of a carbonaceous electrical resistance element, comprising passing therethrough a current of electricity of at least as great cur rent density per unit of cross-section of the resistance element as currents to be carried thereby in service.

19. The process of stabilizing the resistance of a carbonaceous electrical resistance element, comp-rising passing therethrough a current of electricity of at least as great current density per unit of cross-section of the resistance element as currents to be carried thereby in service, for a period of timeat least as long as that to be occupied by any current to be carried thereby in service.

20. The process of stabilizing the resistance of a carbonaceous electrical resistanceelement, comprising heating the said element by passing an electrical current therethrough, to at least as great an extent as curs rents to be carried thereby in service will heat it.

21. The process of stabilizing the resistance of an electrical resistance element having unstable resistance, comprising sending sufiicient electrical current through the ele-- ment to stabilize the resistance thereof for the r uired purpose.

22. i [he process of stabilizing-the resistance of a carbonaceous electrical resistance element, comprising sending sufficient electrical current through the element-to stabilize the resistance thereof for the iequired purpose.

As inventor of the-foregoing I'hereunto subscribe my name, this 21 st day of July,

FREDERICK R. PARKER. Witnesses: V

FnANoEs K. PARKER,

O'rro KIsoHnL. 

